30-40 krag

[original]

I am trying to load up for a 30-40 and 175grain cast 100% ww, powder coated and gas checked. I don't have the powder charge but guessing it was around 25 to 27grains of RL7. I got about 1850fps from it. The charged looked to fill about 50% of the case.
Am I creating a dangerous situation only having half the case filled?
Thanks

[uscra112]

Simple answer is no. RL-7 is perfectly happy at 50% load density.

[todd9.3x57]

what he said.

i use a 165gr ranch dog and 25.5gr of h4198 that goes 1930fps.

[uscra112]

RL-7 is just a shade slower than 4198.

RL-7 is misunderestimated today, IMHO. Time was, when the .222 Remington was the dominant benchrest cartridge, almost all the top shooters were using it. It worked very well for me when I was shooting reduced loads in the .35 Remington, back in the dark ages when I first started casting bullets for myself.

[original]

I was worried about the lack of powder in the case and detonation, never really loaded a case this low before.

[uscra112]

"Detonation" is an urban myth. Smokeless powder cannot detonate. The chemistry is all wrong.

What CAN happen under certain narrow circumstances is that the primer flash drives the bullet into the throat, where it sticks, before the main powder charge ignites. The bullet is now a bore obstruction, and the burn pressures goes through the roof. This can't happen with cast bullets - they are too soft to present much resistance. Another requisite for this phenomenon is slow powders that are hard to ignite. RL-7 is not one of those. Not even close.

Very low loading density, with some powders, can lead to sensitivity of the load to the position of the powder in the case, and hence large variations in muzzle velocity. You are nowhere near that issue with RL-7 at 50% load density.

Do not be tempted to use fillers in your load. Will raise pressures without improving the velocity spread.

The greatest danger in your load regime is the double charge. Most pistol blowups attributed by the ignorant to "detonation" are just double charges of powder that weren't caught before the bullet was seated.

[original]

Thank you everyone for all the great info. The filler was another question I had.

[Outpost75]

I am trying to load up for a 30-40 and 175grain cast 100% ww, powder coated and gas checked. I don't have the powder charge but guessing it was around 25 to 27grains of RL7. I got about 1850fps from it. The charged looked to fill about 50% of the case.
Am I creating a dangerous situation only having half the case filled?
Thanks

No issues with RL7 at 50% fill

[GooseGestapo]

IF you do try a filler, use Dacron pillow stuffing. Works great!
I occasionally use it with #2400 in large rifle cases. It improves accuracy by reducing shot to shot variations by holding powder charge near primer.

Dacron is used as a binder in smokeless powders, and is consumed with combustion. Many other fillers aren’t and can remain in the bore causing a bore obstruction.

Ditto what USRCA112 said!

[uscra112]

I definitely avoid synthetic pillow stuffing after fouling my Dad's .35 Remington with melted residue of the stuff. Bought a full pillow's worth of kapok, which either burns or gets blown out the muzzle. Plenty to share it anyone wants some. I'll pack a small flat-rate box with it. You only pay postage. I haven't used a filler in a load for many years.